layer vs suit of armour

layer

noun
  • An item of clothing worn under or over another. 

  • One of the items in a hierarchy. 

  • A person who lays anything, such as tiles or a wager. 

  • A (usually) horizontal deposit; a stratum. 

  • A shoot of a plant, laid underground for growth. 

  • A single thickness of some material covering a surface. 

  • A mature female bird, insect, etc. that is able to lay eggs. 

  • A hen kept to lay eggs. 

  • one in a stack of (initially transparent) drawing surfaces that comprise an image; used to keep elements of an image separate so that they can be modified independently from one another. 

verb
  • To arrange in layers. 

  • To cut or divide into layers. 

suit of armour

noun
  • A collection of garments, usually made of metal, worn over the body for protection in battle from weapons. 

How often have the words layer and suit of armour occurred in a corpus of books? (source: Google Ngram Viewer )